Safety device for power transmission.



H. B. DIERDORFF.

SAFETY DEVICE FOR POWER TRANSMISSION.

APPLICATION FILED JULY 24.1908. RENEWED MAR. 19,1915.

1,156,397. Patented Oct. 12, 1915.

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HENRY BEECI-IER DIERDOEFF, or, COLUMBUS, 01110, ASSIGNOR TO THE JEFFREYU MANUFACTURING ooMPANY, VA CORPORATION on 01110.

: SAFETY Device For. rowan T'RANsMIssion.

Specification of Letters .Patent.

Applicatibn and July 24, 19081; seriiivo. 445,233. Renewed March 19', 1915. Serial No. 15,573.

To all whom it maywmm; i

Be it knownthat LHENR'Y' B. DInRDoRrF, a citizen of the United States, residing at Columbus, in the county of Franklin and State of Ohio, have invented certain new and useful Improvements in'S'afety Devices for Power-Transmission, of which the following is a specification,reference beinghad therein to the accompanyingdrawing.

This invention relates to safetyfdevices and has for its object to fprovidemeans simply constructed and convenient to use for automatically preventing the transmission of excessive power by a train of power transmitting devices and relieving the other more important parts of tlie mechanism of undue stress. I

To this endlthe invention consists in the provision of an integral collar or washer like part of frangible material having a noncircular aperturelto fit a non-circular part of a shaft and having an interlocking en gagement with a gear, wheel or the like, sleeved loosely upon the shaft, so that the three parts-shaft, washer and sleeve, are held against relative rotation normally, while the relative weakness of the washer insures its breakageand the consequent saving of the other parts when the mechanism is subjected to abnormal stresses.

While my invention may be applied in a great variety of ways, 1 have selected for the purpose of illustration, a mining machine of the kind described and shown in my Letters Patent of the United States No. 684,356 and will describe its manner of use with such a machine.

Figure 1 is a plan view of enough of the parts of a mining machine, similar to that described in the'patent above mentioned, to make clear the manner of using my invention. Figs. 2 and 3 show the worm sleeve which is one of the elements of the safety device proper. Figs. 4 and 5 show the cast iron washer which is another element of the safety device. Fig. 6 is an end View of the shaft 1-'l-. Fig. 7 is a. longitudinalcross section of the safety device with its various parts assembled.

1--1 indicate parts of the bed frame of a. mining machine.

2 indicates the rear plate or platform of the moving carriage, this plate carrying the electric motor (not shown) and the power transmitting gearing connecting the motor with the cutter-chain 3 and also with jthe pinions I which engage racks (not shown) earned by the bed frame for feed mg the carnage backward and forward with respect to the bed frame.

The shaft 5, which is one of the elements of the power transmitting gearing abovere ferred to, is mountedtransverse of the car:

riage platform in the pillow-block bearings 6-45. The shaft "rigidly carries at one end the spur gear wheel? whiclrmeshes with the motor pinion. (not shown). The chain.

sprocket-Wheel Sis rigidly mounted below" the plate 2 upon the vertical stub shafts,

gear wheel IO'and the beveled pinion 11, the

which is drivenbyuneans of thebevele'd latter carried rigidly by shaft 5. p

The transverse shaft-5 also carries" the gearwheel 12 which meshes with the beveled Patentedbct. is, are;

ward so as to disengage the cutters from the coal. A similar shaft 16 arranged at the opposite side of the carriage platform receives power from the transverse shaft 5 through the worm 17 on the latter and the worm wheel 18 which it has mounted-upon its forward end, and serves to rotate the shaft 15 in the opposite direction for feed ing the carriage and cutter mechanism a slowly forward agamst the face of the coal.

Motion is imparted to the shaft 15 from the short shafts 1e and 16 by similar mechanism in each case. In the case of the carriage retracting shaft 14, operative connection is made as follows: The worm-wheel 18 is mounted looselyupon the shaft 15 and engages the worm-sleeve 20 mounted loosely upon shaft 14L. The worm sleeve 20 is made to revolve with the shaft 14 by means of the washer 21. This washer is provided with the lugs 22 which are received by the notches 23 in the outer end of the worm-sleeve 20, and this engagement of the lugs with the notches serves to cause the washer to rotate with the worm. The central aperture 24: of

the washer is rectangular in shape and snugly fits over the square end 25 of the shaft 14. In this manner the washer is likewise caused to rotate with the shaft 14, and the worm sleeve and the shaft 14 are rigidly connected with each other. The nut 26 holds the washer in position against the end of the sleeve 20. .V 1 e The sleeve or hub 19 of the worm wheel 18 constitutes one element of a clutch of which the sleeve 27 splined to the shaft 15 is the other element. Each of the two elements is provided with spiral jaw teeth which engage each other to transmit motion in one direction of rotation when the sleeve 27 is moved into'operative position by means of the usual clutch controlling mechanism 28. When the sleeve 27 is shifted axially in the opposite direction, shaft 16 is similarly connected positively to the shaft 15, and when the motor is rotated the carriage'is slowly fed forward. Washers 21-'21 are made of cast iron and will break if excessive saved from undue stress being put upon having a part circular in cross section and an adjacent part polygonal in cross section, a power transmitting sleeve journaled upon the circular shaft part and provided with oppositely disposed notches inthe end adj acent the polygonal shaft part, and an integral washer having a central aperture poly onal in cross section with its walls adapted' to receive and closely engage the polygonal shaft part and provided with oppositely disposed integral lugs adapted to engage the edges of the notches in the sleeve, the washer Copies of this patent may be obtained for five cents each, by addressing the f Commissioner of Patents.

. Washington, D. G. 

